<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>16110100521</title> 
   <style>
	   #box .h2{color: orange;}
	   #box h2{color: pink;}
	   #h2{color: purple;}
	   .h2{color: green;}
	   h2{
		  color: blue;
	      font-size: 100px;
	   }
   </style>	
   <link rel="stylesheet" href="un_9.css">
</head>

<body>
	<div id="box">
	    <h2 class="h2" id="h2">
		是什么颜色？
		</h2>
	</div>
</body>
</html>
